OLAB AISI 316 stainless steel fittings series 1000 are designed for use in pneumatic and hydraulic systems, where the tightness and mechanical retention of the inserted pipe are dependent on two separate components:
- An O-ring with a washer;
- A cut tapered ring (BCL)
The length of the threaded coupling between the nut and the body allows 3-4 turns to be made before active compression of the BCL starts. This increases the safety of the threaded coupling and always guarantees a sufficient number of engaged threads. Bear in mind that the average locking force of a threaded coupling is supported 60% by the first engaged thread, 30% by the second and 10% by the third, so there should always be at least three threads constantly engaged.
The self-locking effect of the BCL is fundamental, even when the nut loosens accidentally. Since the BCL is elastic with a wide excursion of the inside diameter, and hence the outside diameter as well, there is always a state of traction between the male tread of the fitting body and the female thread of the nut that is determined by the vertical component v of the thrust F exerted by the nut on the BCL . This is the same action as that of traditional self-locking elements such as tapered or toothed spring washers. The advantage in the presence of vibration is evident: constant traction between the threads prevents the fitting from unscrewing.